The present invention relates to a cooling system for an internal combustion engine with an electrically driven coolant pump designed to circulate a coolant through the internal combustion engine and through a radiator designed to dissipate the heat, wherein a safety device is provided which has a device for recognizing cases of emergency and an emergency operating device, wherein the device for recognizing cases of emergency is devised to detect a perturbation in the area of the electrically driven coolant pump.
Usually, the coolant pump for internal combustion engines is directly driven by the internal combustion engine via a driving belt. This entails that the speed of the coolant pump is proportional to the speed of the internal combustion engine. With the commonly utilized radial pumps, the flow rate and with it the required driving power increases superproportionally with the speed. When designing the coolant pump, the range of low speed is critical. As a result, in a conventional coolant pump that is properly designed for the range of low speed, the flow rate in the range of high speed is considerably greater than it would be necessary. That is why the power needed to drive the coolant pump at high speed has to be graded, for the most part, as genuine power loss.
An electrically driven coolant pump whose speed is inherently independent of the speed of the internal combustion engine has the advantage to be capable of adjusting, for each operational state of the internal combustion engine, the minimum flow rate needed in each case. This makes it possible to considerably reduce the energy demand of the coolant pump which becomes particularly noticeable in the range of high speed, low load and when the engine is cold. Wide spread use of electrically driven coolant pumps for internal combustion engines was hereto before hindered by the fact that a coolant pump is an extremely critical component part. In case the coolant pump breaks down, operation of the internal combustion engine has to be stopped immediately in order to prevent destruction due to overheating.